1. Field of the Invention
The present invention relates, generally, to apparatus for making shingles and, more especially, to an improved shake resaw apparatus for converting a rectilinear wooden blank into a pair of oppositely tapered wooden shingles.
2. Description of the Background Art
So-called "shake shingles" are very popular roofing and siding materials in the building trade. Customarily, the same are fabricated from cedar in the form of a tapered shingle having a tip end and a butt end destined for overlapping application to, e.g., the roof of a building structure. All manner and variety of dimensions are employed; nominal sizes ranging on the order of about 24" inches in length, about 10" in width, and tapering from about 3/4-1" at the butt to about 5/8" at the tip.
For many years these shake shingles were hand-split, beginning with a large block of cedar and subdividing it manually into the desired dimensions through a very laborious splitting process. Old-growth cedar was found far preferable to second-growth due to the considerably greater grain tightness of the former, both in respect of the ease of splitting and the resulting product.
With the rapid depletion of old-growth cedar and the need for more efficient methods came mechanization in the manufacture of shake shingles. Sawing machines were developed for converting split blanks into shingles by sawing along a diagonal of the blank. Representative of patented apparatus for this purpose are U.S. Pat. No. 4,291,601 and 3,171,450. These apparatus not only made simpler the manufacture of shake shingles from wooden blanks, they accommodated the problems associated with the use of second-growth cedar in this context as the same tends to be much more open in the grain and the blanks have a tendency toward random curvature, waviness, and general nonuniformity.
While many strides have been made in this regard, the apparatus heretofore proposed themselves tend to be quite complicated in design. The need to resort to complicated, elaborate mechanisms has contributed in turn to equally complicated methods of manufacture and routine maintenance to insure dependable operation.